Smart cards are becoming increasingly more popular for security and personal identification applications. For example, smart cards are currently used for storing sensitive data such as medical records, banking information, etc. In perhaps their most common form, smart cards have a card body which resembles a credit card in size, shape, and thickness, and they may even be made out of similar materials, such as plastic. Yet, rather than simply having a magnetic stripe to store sensitive information (e.g., account numbers, user identification, etc.) as standard credit cards do, smart cards generally include an integrated circuit (IC). The IC not only includes a non-volatile memory for storing such sensitive information, but it may also include a microprocessor for processing this information and communicating with a host device via a card reader, for example. Accordingly, not only can smart cards store more information than magnetic stripe cards, but they also have much greater functionality.
Various protocols have emerged to standardize the operation and communications of devices such as smart cards. One of the earliest of these was developed by the International Organization for Standardization (ISO) and is known as the ISO 7816-X protocol. In particular, this protocol is set forth in ISO documents ISO 7816-1 (Physical Characteristics), ISO 7816-2 (Dimensions and Locations of Contacts), ISO 7816-3 (Electronic Signals and Transmission Protocols), ISO 7816-10 (Electronic Signals and Answer to Reset for Synchronous Cards), and ISO 7816-12 (USB Interface) for example, all of which are hereby incorporated herein in their entirety by reference.
Furthermore, in response to the increasing popularity of the universal serial bus (USB) architecture, increasing numbers of smart cards continue to be developed which operate in accordance with the USB protocol. This protocol is set forth in the Universal Serial Bus Specification, Revision 2.0, Apr. 27, 2000, published by USB Implementers Forum, Inc., which is hereby incorporated herein in its entirety by reference. The USB architecture is particularly advantageous in that it provides a standard “plug and play” interface for devices external to a computer, for example. That is, external peripheral devices can be relatively quickly and easily installed and removed from a host device, such as a computer, without having to open or power down the computer.
As part of most product development cycles for complex computing systems or devices, it is often necessary to produce a functional equivalent of the product before the final product is available. This functional equivalent is typically referred to as an emulator, or hardware emulator (HWE). The HWE allows the application developers for the product to develop and debug software applications for the device while the product engineers finalize and test the physical circuitry and/or components of the product.
With respect to smart cards, a HWE emulator is commonly used to develop, test, and debug new applications which will ultimately become embedded in the final smart card integrated circuit. As such, it is desirable that the HWE provide functionality that matches as closely as possible the real-world functionality of the end product (e.g., a smart card integrated circuit). This can be somewhat difficult with respect to dual-mode smart cards, such as dual ISO/USB smart cards. One such dual mode smart card is described in U.S. Pat. No. 6,439,464 to Fruhauf et al., assigned to the assignee of the present invention, and which is hereby incorporated herein in its entirety by reference.
In particular, to develop embedded applications for a dual-mode ISO/USB smart card device, it is desirable that the HWE replicate as much of the functionality of both modes of operation as possible, including both ISO and USB communications. To accomplish faithful emulation in both modes of operation, the HWE is likely be outfitted with the functional equivalent of a smart card connector. That is, there will preferably be an appendage or cable assembly both electrically and mechanically connected to the main enclosure housing the internal circuitry of the HWE. This appendage then terminates in an adapter or connector which replicates the physical dimensions of the final product.
With typical prior art dual-mode HWEs, when the HWE is used in USB mode with a card form factor, the connector will be flat with metallic pads in the proper geometry so that it may be inserted into an appropriate USB card reader or adapter. The HWE may then recognize that it is to operate in USB mode. Similarly, when used in an ISO mode, the HWE's connector will terminate in a separate appendage (e.g., also with a card form factor) such that when it is inserted into an appropriate ISO card reader the HWE will recognize that it is to operate in ISO mode. In some cases the HWE may include yet another connector (i.e., a dongle form factor with a USB type A plug) also for use in USB Mode.
In other words, typical prior art HWEs require a separate appendage termination type for each of the anticipated end-customer usage models (Cardm, SIM, USB connector, etc.). This is in large part due to the differing electrical properties of the cabling required by the ISO, USB, and other similar specifications. In particular, the USB Specification defines three basic cable types for low-speed, full-speed, and high-speed devices. These cable types differ not only in the materials used for their construction, but also in the way in which they are assembled.
Moreover, while a low-speed USB Device can optionally use the more robust cable that is required for full-speed USB devices, full-speed and high-speed devices may not use the less complicated cabling of a low-speed USB device. This is because the USB cables are carefully specified to provide the best possible environment for transmitting data back and forth between a USB device and the USB reader to which it is connected.
As with USB cables, the construction and materials of an ISO cable are designed to provide the best environment for transmission and reception between a smart card and smart card adapter. However, the relative data rates of ISO differ significantly from those of USB, and thus the cables typically differ as well. Accordingly, because of the various connector types, impedance characteristics, capacitance characteristics, etc., the various cable types typically may not be substituted for one another.
Moreover, with respect to USB devices, transceivers are carefully designed and implemented to provide the best possible signals over the prescribed cables. The same is true of ISO transceivers as well. Thus, as with ISO and USB cable assemblies, data transceivers typically may not be substituted in place of one another between ISO an USB devices.
For the above reasons, smart card HWEs can be cumbersome to implement and use in terms of the requisite cabling and interface circuitry (or “pods”) needed to accommodate multiple connection configurations and/or multiple operational modes.